Mortgage Glossary 2026: Core Terms Every Loan Officer Must Be Able to Explain

Being able to explain mortgage terms clearly is a basic competency. Borrowers are making the largest financial decision of their lives. When you hesitate on a definition or get it wrong, trust erodes immediately. These are the terms that matter most in day-to-day origination.

Loan Structure Terms

• ✦APR: annualized cost of the loan including rate, points, and certain fees; always higher than the note rate
• ✦DTI: debt-to-income ratio; front-end is housing expense divided by gross monthly income; back-end includes all monthly obligations
• ✦LTV: loan-to-value ratio; loan amount divided by the lesser of appraised value or purchase price
• ✦CLTV: combined LTV; includes all liens; relevant when a second mortgage or HELOC is present
• ✦Amortization: the schedule of principal and interest payments that retires the loan over its term

Cost and Rate Terms

• ✦Discount points: prepaid interest paid at closing to buy down the rate; 1 point equals 1% of loan amount
• ✦Origination fee: lender charge for processing the loan; may include points or flat fees
• ✦Par rate: the interest rate at which the lender neither charges points nor pays a rebate to the borrower
• ✦Rate lock: a contractual agreement fixing the interest rate for a specified period between application and closing
• ✦APR vs. rate: the rate is the cost of borrowing; the APR wraps in fees to give a total annualized cost

Underwriting Terms

• ✦AUS: automated underwriting system; DU is Fannie Mae, LPA is Freddie Mac; outputs are Approve/Eligible or Refer
• ✦Conditions: items the underwriter requires before clearing the loan; PTAs are prior-to-approval, PTDs are prior-to-docs
• ✦Clear to close: all underwriting conditions have been satisfied and the loan is approved for funding
• ✦Overlay: a lender requirement stricter than the agency minimum; lenders can always go tighter, never looser
• ✦Suspense: file is on hold pending additional documentation; this differs from a denial